I am working on rebuilding a WPC display board HV section. In the schematics it shows R7 as a 0 OHM jumper. Parts list shows a 56 OHM resistor. My boardhas is the 56 OHM resistor installed.
Has anyone noticed this?
Do I install a jumper in place of the resistor? Or leave the resistor?
My board has suffered from heat, so trying to do this right the first time! 
Frankly it depends upon the display you are hooking to the machine. If it's a Babcock, it uses the 12v line which is regulated by a combination of R7 and D8. Other plasma DMDs don't use the 12v line so you normally have a jumper/zero ohm resistor in R7 and nothing in D8. So for Babcock you need both R7 and D8.
For greatest compatibility install the 56 ohm resistor and diode in D8. Though R7 is usually not part of the rebuild kit because it doesn't normally go bad unless the board is really scorched. But if that happened you'd have bigger problems (doesn't look it from your photo.)
viperrwk
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